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stagecraft and machinery

...casters so that it can be quickly rolled onstage and offstage; the jackknife stage, similar to the wagon except that it is anchored at one corner from which it pivots onstage and offstage; and the
revolve, or turntable, in which several settings are built on a huge circular platform that is turned so that only the appropriate setting may be seen through the proscenium. In each of these, the...